As shown in FIG. 1, a known diode 10 includes an n-doped base layer 2 having a cathode side 23 and an anode side 24 opposite the cathode side 23. On the anode side 24, a p-doped anode layer 25 is arranged, and a metal layer which functions as an anode electrode 4 is arranged on top of the p-doped anode layer 25. A higher (n+) doped cathode buffer layer 22 is arranged on the cathode side 23. A metal layer in form of a cathode electrode 3 is arranged on top of the (n+) doped cathode buffer layer 22. On the anode side 24, there are defect centers, which can be created by a Hydrogen or Helium irradiation, arranged near the junction in the p-doped anode layer 25. By the defect layer 45, reverse recovery current is reduced and thereby, the power losses and softness of the device improved. However, leakage current is high in a diode with such a defect layer 45, and the amount of leakage current varies strongly with the position of the peak of the defect layer 45.
Because of the high leakage, the devices cannot operate above 125° C. As the doping profile is very steep, a small variation in the doping profile due to a spread in production results in large differences of other relevant device parameters after the irradiation. To maintain the production yield high, a tight control of both the doping profile and irradiation energy are required.